Wall breaching apparatus and method

ABSTRACT

Wall breaching apparatus and methods utilizing shaped charges for penetration of walls of buildings and other structures for rescue, escape, or military operations.

This application claims the benefit of U.S. Provisional Application No.60/501,815, filed Sep. 10, 2003.

The full disclosure of the parent provisional application isincorporated herein by reference.

FIELD OF THE INVENTION

This invention provides a portable easily deployable apparatus for wallbreaching in both civilian and military environments. The apparatus hasparticular use in rescue operations where persons may be trapped insidebuildings or in providing escape from an enclosed environment. Otheruses include forced entry into buildings or other structures.

BACKGROUND OF THE INVENTION

Conventional shaped charges can be used to defeat targets such asreinforced concrete and typical structural materials such as brick,stone, wood and the like. However, conventional apparatus for breachingtargets lack the ability to attack widely variable targets, aretypically heavy and cumbersome to carry. Typical prior art devices areexemplified by U.S. Pat. No. 3,838,643 to Austin et al.; U.S. Pat. No.4,430,939 to Harrold; U.S. Pat. No. 4,905,601 to Gabriel et al.; U.S.Pat. No. 5,036,771 to Alford; and U.S. Pat. No. 5,524,546 to Rozner etal.

BRIEF DESCRIPTION OF THE INVENTION

The present invention includes several broad embodiments. A first broadembodiment includes a kit that can be used for constructing a wallbreaching structure. The kit is made up of a plurality of linear shapedcharges; a plurality of block explosive charges; and a plurality ofconnecting members for connecting any of the shaped charges and theblock explosive charges to others of the shaped charges and the blockexplosive charges; typically the shaped charges and the block explosivescan be configured into a multiplicity of different arrangements andconnected together to form a wall breaching structure.

A second broad embodiment includes an apparatus produced from the kitthat includes, a plurality of linear shaped charges; a plurality ofblock explosive charges; and a plurality of connecting members forconnecting any of the shaped charges and the block explosive charges toothers of the shaped charges and the block explosive charges; typicallythe shaped charges and the block explosives can be configured into amultiplicity of different arrangements and connected together to form awall breaching structure.

A third broad embodiment includes a method for breaching a structuresuch as a wall and the like with a reduced weight charge. The methodprovides for simultaneous cutting of rebar and blast of an opening usinga light shaped charge typically less than about 60 pounds. Typically themethod includes the steps of providing a metal lined linear shapedcharge having a weight of less than about 60 pounds; placing the linearshaped charge against the non-homogeneous reinforced aggregatestructure, the structure having a reinforcement member; and explodingthe linear shaped charge to generate a metal jet and a blast wave,wherein the metal jet cuts the reinforcement member at at least onelocation and the blast wave creates an opening in the aggregatematerial, and wherein the cutting of the reinforcement member and thecreation of the opening occur substantially simultaneously.

A fourth broad embodiment includes provides for using non-continuouspolygon shaped wall breaching apparatus. The method includes the stepsof placing an explosive charge configured to define a portion of aperimeter of an opening to be formed against the non-homogeneousreinforced aggregate structure, the structure having a reinforcementmember; and exploding the explosive charge, wherein a blast created bythe explosive charge creates an opening in the aggregate material, cutsthe reinforcement member in one location, and bends the reinforcementmember substantially at the portion of the perimeter of the opening in adirection of the blast, such that a person can travel through theopening thereby created.

A fifth broad embodiment includes an initiation mechanism for firing alinear shaped charge. The mechanism typically includes a linear shapedcharge having a metal liner; a plurality of detonators attached to thelinear shaped charge; and a mechanism for simultaneously igniting theplurality of detonators; wherein the simultaneous ignition of theplurality detonators creates a substantially planar detonation wave. Ayet further embodiment of the invention includes a method for making asubstantially planar detonation wave. One method includes creating asubstantially planar detonation wave, by the steps of providing a linearshaped charge having a metal liner; attaching a plurality of detonatorsto the linear shaped charge; and igniting the plurality of detonatorswith a mechanism for simultaneously igniting the plurality ofdetonators; and wherein the simultaneous ignition of the pluralitydetonators thereby creates a substantially planar detonation wave.Another method for igniting a linear shaped charge includes the steps ofproviding a linear shaped charge having a metal liner; a first detonatorattached to the linear shaped charge; a second detonator attached to thelinear shaped charge; an intermediate detonator attached to the linearshaped charge and disposed between the first detonator and the seconddetonator; and a mechanism for simultaneously igniting the first,second, and intermediate detonators, and wherein the simultaneousignition of the plurality first, second, and intermediate detonatorsthereby creates a substantially planar detonation wave.

Typically the methods according to the invention provide that the metaljet and/or explosive charge cuts at least about 10% to 75% of the cutreinforcement members at one location and the remainder at twolocations. In some embodiments the where double rebar is used the metaljet and/or explosive charge cuts at least two of the cut reinforcementmembers at one location and the remainder at two locations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is set of two diagrams depicting extended (FIG. 1A, top diagram)and partially folded (FIG. 1B, bottom diagram) of an apparatus accordingto the invention.

FIG. 2 is set of schematic diagrams depicting a frontal view (topdiagram) and a side view (bottom diagram) of the linear chargearrangement according to the invention.

FIG. 3 illustrates the effect of standard linear shaped chargeinitiation on liner collapse factors as in the prior art.

FIG. 4 illustrates the effect of multiple initiation points on waveshaping for the apparatus according to the invention.

FIG. 5 illustrates is a frontal view of wave fronts for simultaneousinitiation using hemispherical wave shaper initiations.

FIG. 6 illustrates side (left diagram) and frontal views (right diagram)for pyramidal wave shaper initiation.

FIG. 7 illustrates a four point initiation configuration.

FIG. 8 illustrates detonating cord down-line connectors and how theywould mate.

FIG. 9 illustrates a complete initiation system with hemispherical waveshapers, three point initiation, down-line connectors and central hub

FIG. 10 illustrates a top view of a typical wall breaching apparatusaccording to the invention and a side view of a linear shaped charge.

FIG. 11 illustrates a schematic for a typical “basic” configuration asdiscussed herein.

FIG. 12 illustrates a schematic for a “concept L” configuration asdiscussed herein.

FIG. 13 illustrates a schematic for a “concept C” configuration asdiscussed herein.

FIG. 14 illustrates a schematic for a “concept parallel” configurationas discussed herein.

FIG. 15 illustrates a schematic for a “concept Y” configuration asdiscussed herein.

DETAILED DESCRIPTION OF THE INVENTION AND BEST MODE

The wall breaching apparatus typically includes a quickly deployed,fully contained, modular explosive charge. The wall breaching apparatustypically includes a folding template, linear shaped charges, integralinitiation system, and attachment system. The attachment systemtypically is a mini-stun gun attachment or a (support) prop pole to holdthe system in place. Other methods for attachment known in the art maybe used. There are two different embodiments for the folding templatethat will trade-off deployment time and cost/weight.

The wall breaching apparatus is modular so that it can be used againstdiffering target wall designs. One embodiment of a typical wallbreaching apparatus (typically six segments forming a hexagon,approximately 23 pounds net explosive weight) will breach the concreteand both layers of rebar contained in an 8 inch thick double layerreinforced poured concrete wall producing at least a 36 inch diameterhole. A typical three segment system (three segments separated by 120degrees, approximately 12 pounds net explosive weight) will breach atriple layer brick wall. A typical two segment system (two segmentsseparated by 180 degrees, approximately 8 pounds net explosive weight)will breach CMU and brick-on-block walls.

Detailed below are typical deployment embodiments and methods, designsfor the templates, initiation systems, and explosive charges.

The invention provides for a kit that can be used for constructing awall breaching structure. The kit is made up of a plurality of linearshaped charges; a plurality of block explosive charges; and a pluralityof connecting members for connecting any of the shaped charges and theblock explosive charges to others of the shaped charges and the blockexplosive charges; typically the shaped charges and the block explosivescan be configured into a multiplicity of different arrangements andconnected together to form a wall breaching structure.

The shaped charges contained in the kit are linear shaped charges. Thestandard cross sectional design of a typical linear shaped charge hasstraight sides extending from a single included angle. This conventionallinear shaped charge design is economical to produce but is not the bestbased on weight and performance. The design of the shaped charges forthis wall breaching system follow convention for high performance designof conical shaped charges typically used for armor defeat in militaryapplications, instead of the convention for linear charges. Because ofthis the choice available for cross section designs is much more varied.The cross sections in this case can include the following patterns:straight-sided, “trumpet” shaped, “tulip” shaped, and “bi-conic” shaped.Using these additional shapes it is possible to obtain betterperformance than the standard straight-sided approach.

The materials used to construct the shaped charge liners useful in thiswall breaching kit can include: copper, tantalum, silver, gold,aluminum, composites of metals, alloys of these metals, composites ofthese metals with fluorocarbon polymers, other malleable metals, glassand mixtures thereof.

The block explosives used in the kit can typically be high velocityexplosives such as the standard M112 demolition block which consists of1.25 pounds of plastic explosive. Other block or bulk explosive chargescould be used, including: one pound TNT demolition blocks, cartridges ofeither military or commercial dynamite, cast pentolite boosters,flexible sheet explosive or detonating cord charges.

The connecting members and other supporting or enclosing parts of thekit or apparatus according to the invention are typically constructed oflightweight and strong materials with the desire being to minimize theamount of fragmentation created during the detonation of the wallbreaching charges. These construction materials may include: woundcarbon fiber, carbon fiber composite, an aluminum/polymer composite,fiberglass or other polymer composite. The connecting members will beable to deploy the explosive charges from a folded, compact arrangementinto an extended position in the final moments before breaching the walltarget. The connecting members will perform this deployment by eitherunfolding or extending by applied gas pressure or mechanical force.

Another aspect of the invention is an apparatus produced from the kitthat includes, a plurality of linear shaped charges; a plurality ofblock explosive charges; and a plurality of connecting members forconnecting any of the shaped charges and the block explosive charges toothers of the shaped charges and the block explosive charges; typicallythe shaped charges and the block explosives can be configured into amultiplicity of different arrangements and connected together to form awall breaching structure. The constituents of the apparatus aretypically those described earlier for the kit.

Deployment Method

A preferred embodiment such as an umbrella template is designed forquick deployment and the reduction of time-on-target. FIG. 1 shows theumbrella template with attached explosive charges. The following stepsare used to deploy the umbrella template version of the modularbreaching system:

-   1. Pull contents out of a carrying bag (not shown)-   2. Approach wall;-   3. Place front end of device on wall while making sure that the    (support) leg is firmly planted. In poor weather conditions stakes    may be used;-   4. Deploy umbrella template by pushing sleeve towards wall;-   5. While holding deployed device against wall, anchor charge to the    wall by firing two stud guns (not shown) through attachment pads    (not shown) if necessary;-   6. Prime central hub 111 with either one or two standard detonator    systems (e.g. time delay firing unit, shock-tube, etc); and-   7. Retreat to safe area and fire breaching charge.

Another embodiment of the invention provides for a Compact Template 200that consists of three (3) jointed sections shown either as 211 or 213in Diagram 2A. Diagram 2B shows the jointed sections 211 or 213partially assembled. Individual shaped charges 201 are shown as part ofthe set. See diagrams 2A, 2B, 2C and 2D in FIG. 2. The three sectionscan be joined by pins 215 to create a hexagon (diagram 2C) that can beused to make a thirty-six inch hole in a rebar reinforced concrete wall,lesser sections can be used in configurations described herein, or asingle section can be deployed against smaller targets, such as lesserwalls. Diagram 2D is a side view of the assembly. The following stepsare used to deploy the compact template version of the modular breachingsystem:

-   1. Pull contents out of carrying bag (not shown);-   2. Assemble the hexagon or other figure;-   3. The six sides are folded in the middle via hinge, unfold the    hinge and slide lock pin in place;-   4. Connect the six sides together to form a hexagon, hook inside and    slide pin on outside (note hook is integral and slide pins are    permanently attached);-   5. Attach the two mini-stud guns,-   6. Connect the detonation cords from the distributor into the legs    of the hexagon;-   7. Carry assembled hexagon to the wall;-   8. While holding device against wall, anchor hexagon to wall by    firing two or more stud gun studs (not shown) through attachment    pads (not shown);-   9. Prime central hub 111 with either one or two standard detonator    systems (e.g. time delay firing unit, shock-tube, etc);-   10. Retreat to safe area and fire breaching charge.

Referring again to FIGS. 1A and 1B, the umbrella type system 100includes a leg support made up of a leg base 101, a straight leg portion103, connector 105, and angled leg 107. These provide support to hub 111which in turn provides support to linear shaped charges 109 withconnection members 113 that are connected to both the charges 109 andthe hub 111. End stop 115 and stop connector 117 complete the assembly.

Initiation System for the Wall Breaching Apparatus

The initiation mechanism of the wall breaching apparatus is a keycontributor to its enhanced performance over standard linear shapedcharges. A simultaneous line initiation along the entire back of thecharge allows for the classical collapse sequence of the angled liner.With this method, the detonation wave planes from a circular pattern atthe point source into a horizontal line. This planar detonation wavesweeps across the angled liner from the apex to the base of the liner'striangular shape. This collapse profile allows for the plasticallydeformed metal from both sides of the liner to impact at the stagnationpoint and jet efficiently towards the target. The cross-sectional viewof this reaction in the wall breaching apparatus is very similar to thatof a classical conical shaped charge.

This contrasts with the detonation methodology of a standard linearshaped charge. This device is normally initiated from the ends of eachcharge as shown in FIG. 3. The detonation front for such an initiationtravels perpendicular to the angled liner. This detonation method doesnot permit the Chapman-Jouguet (CJ) front to collapse the liner in thedesired manner, from the apex to the base. This side on method wouldinitiate collapse at the front edge of the CJ front. This collapse pointmay not be the apex of the liner. The side on wave would also induce anX and Y component into its jet's velocity vector. The X component, jetmomentum parallel to the target surface, would represent lostpenetrating ability.

The initiation method of the wall breaching apparatus strives to achievean apex to base collapse of the liner in a direction that is tangent tothe target as shown in FIG. 4. This collapse progression of the wallbreaching apparatus liner is like that of a conical shaped charge. Thismaximizes the penetrating ability of the charge. In order to achieve aplanar detonation wave shape, simultaneous multipoint initiation isused. The detonation front from the multiple initiation sites collidemidway between the points. This integrated wave approaches a planar formmuch faster than a detonation wave produced from a single initiationpoint. This technique has a similar effect to wave shaping in conicalcharges. FIG. 4 shows four detonators 401 and boosters 403 that are usedto fire a linear shaped charge 407. The detonators 401 produce four wavefronts 405 that combine to produce a linear wave front perpendicular tothe target. The wave fronts 405 move much more linearly from the apex409 of the linear shaped charge 405 to the bottom 411 in the Y directionthan the prior art.

The initiation method used for wall breaching apparatus assumes asimultaneous line initiation directly above the apex of the liner alongthe entire length of each segment of the system. This line initiationmethod is crucial to the charge performance. An instantaneous detonationwave that collapses the liner from apex to base results in a jet that isoriented directly at the target. This line initiation forms a detonationwave that begins as a small circle expanding outward through theexplosive towards the liner. As this circle expands with time, thecircumference of the front expands radially from the initiation point.From the reference location of the liner, the expanding shape of thewave begins to flatten and become somewhat planar. This flattened wavesweeps the liner from apex to base. The time related contours of thiswave can be seen below in FIGS. 4, 5, and 7. As the detonation frontsweeps the liner, it transfers momentum into the liner material. Theliner material is then accelerated as a jet inward towards a linear axisprogressing from the apex to the base. The jets collide at a point alongthis axis called the stagnation point. At the stagnation point, themomentum is again redirected towards the base along the axis. Thisredirected jet is oriented perpendicular to the target for achievingmaximum penetration.

Achieving an instantaneous line initiation along the back of the chargeis not easily accomplished. Referring now to FIGS. 6A and 6B, thesesetups use sections of Primasheet® explosive cut in the form ofequilateral triangles. These triangles contain a sequential series ofholes cut in them at regular intervals. The spacing between each ofthese holes also forms a progression of equilateral triangles. Theseholes force a circular shaped detonation front to curve around them. Theequidistance around each equilateral triangle force the detonation frontto assume a planar shape as it moves down the sheet.

A planar wave shape can also be achieved with simultaneous multi-pointinitiation. Collisions of multiple circular shaped detonation frontscongeal into an integrated wave front that has a flattened appearance asit moves through the remaining un-reacted explosive. The spacing betweenmultiple initiation points determines the degree of planarity that isachieved in the newly formed wave. This can be observed in the drawingbelow. This assumes that the detonation velocity is constant throughoutthe explosive, as is most often the case.

Referring again to FIG. 3, a standard linear shaped charge 301 that isend initiated by detonator 303 and booster 305 results in a detonationwave 306 that engulfs the liner 307 (see liner apex 311 and liner base313) in an enlarging circular expansion focused from the point source309 and expanding along the longitudinal axis of each charge. This wavegeometry results in jets that move in an angular direction to thetarget. This angular direction contains vector components that are bothparallel and at right angles to the intended target. For futurediscussions, the parallel to target directions will be defined as the“X” direction and the perpendicular to target direction will be definedas the “Y” direction. The shape of this detonation front results in aunique jet shape. The jet vector from the top portion of the liner ismoving primarily in the “X” direction. Accordingly, the jet vector fromthe base of the liner is moving mainly in the “Y” direction. Thefocusing jet from the liner collapse is moving in a gradient from theapex to the base. It would appear as an inverted angle traveling at anincidental angle to the liner. The jet's gradated, angular formationhelps to explain the comparatively short length jets that result fromend initiating a standard linear shaped charge.

This phenomenon was observed in a test performed in a small mockup ofhexagonal breaching charge using standard 2,000 grains/foot linearshaped charge, loaded with 70/30 Octol. This test device was shot at a{fraction (1/2)} inch thick steel target. The six segments of the chargewere sized to fit inside a 4 inch inscribed circle. Each segment wassimultaneously initiated at its midpoint. This initiation techniqueresulted in collision of 12 separate and inverted angular jets at thecorners of the hexagon. Because of the inverted angular shape of thecolliding jets, expanded penetration of the target was achieved. Theinitial collisions occurred along the “Y” axis of the angular liner.After the bottom of the center point of the jets collided along theliner axis, the collisions began to occur outward and away from theliner's centerline. These collisions resulted in expanded penetration inthe target opposing the connecting corners of the assembled hexagon.

The present invention uses multiple firing points that enhance theplanarity of the detonation wave and maximize the “Y” component of thejet.

Referring now to FIG. 5, hemispherical shaped boosters 501 between thedetonators 503 and planar shaped charge 505 are one embodiment that canexpand the distributed detonation front area from multi-point initiationalong the charges back. These hemispheres 501 would contain a phenolicmaterial or similar acting material inside its interior to prevent theshock wave from passing straight through the booster in a sphericalshape. The explosive would comprise a shell configuration 507 around thehalf circle's perimeter. At the charge contact point, the detonationfrom would be in the shape of a ring. As the front 509 expands inwardand outward from the ring, the colliding waves result in a greatlyflattened shape. The wave which started at the top 511 of the linearshaped charge is much flatter in appearance when it reaches the bottom513 than single point initiation in the same three locations.

Another shape with a unique advantage in wave shaping is a pyramid shapewhose bottom side is at the width of the top of the charge hassymmetrical advantages along both the charges cross-section and length.See FIG. 6A (cross sectional view) and 6B (side view). In theconfiguration shown 600 a plastic fixture holds the linear shaped charge603 and detonator holders 604. The linear shaped charge is fired withpyramidal wave shapers 605 between the detonators 607 and the highexplosive 609 of the linear shaped charge 603. Typically a copper liner611 is used with the shaped charge as shown. Liner apex 613 and linerbase 615 are typical as shown. Optionally legs 619 may be used to offsetthe linear shaped charge 603. Attachment points 621 are those typicallyused in the art.

Another configuration for producing satisfactory wave shaping is to usemultiple point initiation as seen in FIG. 7. In this case fourdetonators 701 are used per wall breaching apparatus section 700. Forsix sections this results in 24 total detonators crimped to detonatingcord leads. Each section of four cords is typically connected to asingle cord lead using custom down-line connectors. These connectorsensure an explosive train from the single 150 grain cord to the four 50grain cords. The six 150 grain cords are embedded into the central huband are initiated by a Primasheet® booster and the firing devicedetonator. This embodiment uses boosters 705 between detonators 701 andlinear shaped charge 703. The top of the charge is at 709 and the bottomat 711. The combined wave shape 713 is much more planar and results fromthe combination of waves from the multiple detonation points 715.

FIG. 8 is a schematic showing cord line connectors 801 and how theywould mate from the central hub 803 for three detonation points perlinear shaped charge.

FIG. 9 illustrates an eight sided polygon configuration 900 with eightlinear shaped charges 901, three hemispherical wave shapers 903 andassociated detonators, central hub, and down line connectors 907.

Referring now to FIGS. 10A and B, these illustrate a four point polygonconfiguration 1000 with eight linear shaped charges 1001, fourdetonators 1003, central hub 1005, and down line connectors 1007. Ablown up view of the linear shaped charge 1001 is shown in FIG. 10Bhaving a liner 1011, enclosure 1013, and explosive 1015.

One embodiment for the wall breaching apparatus 1100 is a set of sixlinear shaped charges 1101 arranged in a hexagonal shape. Thisembodiment is the basic embodiment. See FIG. 11. The charge will beinitiated at multiple points on each linear charge in an effort tomaintain a planar shock wave during the liner collapse event. Connectionmembers 1103, central hub 1105 and leg 1105 provide support.

A preferred material for the shaped charge liner is copper, howeverother materials such as those listed above may be used. A preferred highexplosive for the wall breaching apparatus is PBX-9501. This explosivewas selected for its favorable combination of high detonation velocity,good manufacturability, and good sensitivity characteristics. Otherexplosives useful with the invention include Octol, Composition A,composition B, LX-14, PAX compositions and the like. Preferably a lightweight material such as a plastic material (e.g. polymethylmethacrylate) is used to encase the high explosive of the wall breachingapparatus. Other polymeric materials useful for encasing the highexplosives include polyethylene, polypropylene, fiberglass, carbon fibercomposites, and mixtures thereof.

Typical high strength materials that can be penetrated by the inventioninclude 7000 psi unconfined compressive strength concrete and 50 Ksiyield strength reinforcing steel.

The modular breaching system according to the invention is able todefeat concrete, concrete with single rebar, or concrete with doublerebar in a single shot. Further this system can be tailored easily inthe field to suit the specific target. This reduces its weight andincreases the speed of deployment. The modular breaching system is basedon the penetrating capabilities of linear shaped explosive charges. Thisis the basic unit of explosive power that is used to breach the target,but this new particular breaching charge now opens up the ability tochange the fundamental approach to wall breaching, particularly hardtargets like reinforced concrete, to greatly reduce weight of thebreaching system.

The current approach to wall breaching of reinforced concrete targets isto cut a roughly circular hole with a penetrating explosive charge,usually sections of linear shaped charge. This is shown below in what istermed the “Basic” configuration (See FIG. 11). While this charge ishighly effective against the reinforced concrete wall targets (assumingthe explosive charge of the linear shaped charges clear the opening) theoverall charge is very heavy due to the high weight necessary inpenetrating charges. This current design to produce a 36″ diameter holeuses approximately 108 to 113″ of linear shaped charge. Concept basiccan weight up to about 60 lbs.

This embodiment is based on the assumption that it is required to cutboth ends of the rebar in the wall in order to effectively breach thetarget. But this is simply not the case. If the penetrating charge canbe counted on to reliably cut the rebar in the wall then it is reallyonly necessary to cut one end of the rebar. The remaining long pieces ofrebar will be bent out of the way by the blast effect of the highexplosive in the linear shaped charge or in additional bulk explosives.Typically the bulk explosives are of much lower weight per unit than thelinear shaped charges. This means that by using the present invention indifferent geometric shapes that are designed to cut only one end of therebar the remaining wall section can be fractured and cleared using bulkexplosive charges (such as composition C-4 plastic explosive) that arefired substantially simultaneously with linear shaped charges. Discussedbelow are several different embodiments of the modular breaching systemthat utilize this methodology and their associated characteristics suchas the expected reduction in weight. All of these designs utilize therapid deployment mechanism and hub described elsewhere in thisdisclosure as shown in the figures herein.

A further embodiment of the invention provides for using non-continuouspolygon shaped wall breaching apparatus. The method includes the stepsof placing an explosive charge configured to define a portion of aperimeter of an opening to be formed against the non-homogeneousreinforced aggregate structure, the structure having a reinforcementmember; and exploding the explosive charge, wherein a blast created bythe explosive charge creates an opening in the aggregate material, cutsthe reinforcement member in one location, and bends the reinforcementmember substantially at the portion of the perimeter of the opening in adirection of the blast, such that a person can travel through theopening thereby created. Typical non-continuous polygon shaped apparatusis illustrated in FIGS. 12-15.

First is “Concept L” 1200 shown in FIG. 12. This embodiment 1200 usesfour (typically 18′) linear shaped charge 1201 sections arranged in an“L” shape associated with two blocks of C-4 plastic explosive 1202 toclear the remainder of the hole and push the rubble and rebar out of theway. Support is provided by connection members 1203, hub 1205, and leg1207. The designed arrangement and simultaneous detonation of theexplosive charges will cause colliding shock waves to produce fracturesin the concrete between the charges and break up the concrete enoughsuch that the bulk C-4 charges can clear the hole out. This principle ofcolliding shock waves is repeat in each of the embodiments described.This embodiment produces an approximately 36″ square hole and utilizes72″ of linear shaped charge explosive charge. This reduces the weight toapproximately 80% of a fully circular “Basic” configuration.

“Concept C” 1300, shown in FIG. 13, utilizes three 18″ linear shapedcharges 1301, two bulk explosive charges 1302, connection members 1303,hub 1305, and leg 1307 as shown. This embodiment produces a morecircular hole that is approximately 31″ in diameter and uses thecolliding shock wave phenomena described above. This embodiment uses atotal of 54″ of linear shaped charge and therefore will weighapproximately 60% of the Basic configuration.

Referring now to FIG. 14, “Concept Parallel” 1400 typically utilizesfour about 13-14″ linear shaped charges 1401, two bulk explosive charges1402, connecting member 1403, hub 1405, and leg support 1407 as shown.This embodiment produces a roughly circular hole that is about 30 to 36″in diameter and uses the colliding shock wave phenomena described above.This embodiment uses about a 52 to 56″ of linear shaped charge andtherefore will weigh approximately 65% of the Basic configuration. Thehole diameter is about 113″. A typical reinforced rebar spacing is about8″.

The concept parallel typically cuts the reinforcing bars in reinforcedconcrete in one and/or two places per rebar, however not all of the cutrebars are cut twice as is the case in a circular or polygonal wallbreaching system. In this system two parallel linear shaped chargesprovide double cutting to only some rebars. The system is typicallyplaced against a wall to be breached so that the parallel linear chargesare at about a 45° angle from the vertical and the explosive chargeinitiated. The angle of application may range from about 35° to 55°degrees. Although some of the bars are only cut once the wall is stillpenetrated either by the linear charges alone or with the aid of one ormore additional lightweight explosive charges that blow out the wall.This system is typically of lower weight than a circular or polygonalwall breaching system.

Referring now to FIGS. 15A and 15B, “Concept Y” 1500 utilizes threelinear shaped charges 1501, connecting members 1503, hub 1505, and legsupport 1507 as shown. This embodiment is not designed for breachreinforced concrete but rather is for triple course brick orbrick-on-block target walls. This embodiment produces a roughly circularhole that is approximately 30″ in diameter. The vertical imprint isshown in FIG. 15B. Colliding shock wave phenomena is much less importantin these types of targets. This embodiment will weigh approximately 50%of the Basic configuration.

Another embodiment of the invention includes a method for breaching astructure such as a wall and the like with a reduced weight charge. Themethod provides for simultaneous cutting of rebar and blast of anopening using a light shaped charge typically less than about 60 pounds.Typically the method includes the steps of providing a metal linedlinear shaped charge having a weight of less than about 60 pounds;placing the linear shaped charge against the non-homogeneous reinforcedaggregate structure, the structure having a reinforcement member; andexploding the linear shaped charge to generate a metal jet and a blastwave, wherein the metal jet cuts the reinforcement member at at leastone location and the blast wave creates an opening in the aggregatematerial, and wherein the cutting of the reinforcement member and thecreation of the opening occur substantially simultaneously.

A further embodiment includes an initiation mechanism for firing alinear shaped charge. The mechanism typically includes a linear shapedcharge having a metal liner; a plurality of detonators attached to thelinear shaped charge; and a mechanism for simultaneously igniting theplurality of detonators; wherein the simultaneous ignition of theplurality detonators creates a substantially planar detonation wave. Themechanism for simultaneously igniting the linear shaped chargestypically includes a capacitive discharge pulse power unit, anexplosively driven power supply that provides an electrical pulse, andother electrical pulse generators known in the art the associatedwiring.

A yet further embodiment of the invention includes a method for making asubstantially planar detonation wave. One method includes creating asubstantially planar detonation wave, by the steps of providing a linearshaped charge having a metal liner; attaching a plurality of detonatorsto the linear shaped charge; and igniting the plurality of detonatorswith a mechanism for simultaneously igniting the plurality ofdetonators; and wherein the simultaneous ignition of the pluralitydetonators thereby creates a substantially planar detonation wave.

Another method for igniting a linear shaped charge includes the steps ofproviding a linear shaped charge having a metal liner; a first detonatorattached to the linear shaped charge; a second detonator attached to thelinear shaped charge; an intermediate detonator attached to the linearshaped charge and disposed between the first detonator and the seconddetonator; and a mechanism for simultaneously igniting the first,second, and intermediate detonators, and wherein the simultaneousignition of the plurality first, second, and intermediate detonatorsthereby creates a substantially planar detonation wave. More than threedetonators than those outlined above may be used.

While the forms of the invention herein disclosed constitute presentlypreferred embodiments, many others are possible. It is not intendedherein to mention all of the possible equivalent forms or ramificationsof the invention. It is to be understood that the terms used herein aremerely descriptive, rather than limiting, and that various changes maybe made without departing from the spirit of the scope of the invention.

1. A kit for constructing a wall breaching structure, the kitcomprising: a. a plurality of linear shaped charges; b. a plurality ofblock explosive charges; and c. a plurality of connecting members forconnecting any of the shaped charges and the block explosive charges toothers of the shaped charges and the block explosive charges; andwherein the shaped charges and the block explosives can be configuredinto a multiplicity of different arrangements and connected together toform a wall breaching structure.
 2. A wall breaching apparatuscomprising: a. a plurality of linear shaped charges; b. a plurality ofblock explosive charges; and c. a plurality of connecting members forconnecting any of the shaped charges and the block explosive charges toothers of the shaped charges and the block explosive charges; andwherein the shaped charges and the block explosives can be configuredinto a multiplicity of different arrangements and connected together toform a wall breaching structure.
 3. A method of breaching anon-homogeneous reinforced aggregate structure, the method comprising:a. placing the linear shaped charge against the non-homogeneousreinforced aggregate structure, the structure having a plurality ofreinforcement members; and b. exploding the linear shaped charge togenerate a metal jet and a blast wave, and wherein the metal jet cuts atleast one of the cut reinforcement members at one location and theremainder at two locations and the blast wave creates an opening in theaggregate material, and wherein the cutting of the reinforcement memberand the creation of the opening occur substantially simultaneously. 4.The method according to claim 3, wherein the metal jet cuts at leastabout 10% to 75% of the cut reinforcement members at one location andthe remainder at two locations.
 5. The method according to claim 3,wherein when double rebar is used the metal jet cuts at least two of thecut reinforcement members at one location and the remainder at twolocations.
 6. A method breaching a non-homogeneous reinforced aggregatestructure, the method comprising: a. placing an explosive chargeconfigured to define a portion of a perimeter of an opening to be formedagainst the non-homogeneous reinforced aggregate structure, thestructure having a reinforcement member; and b. exploding the explosivecharge, and wherein a blast created by the explosive charge creates anopening in the aggregate material, cuts the reinforcement member in onelocation, and bends the reinforcement member substantially at theportion of the perimeter of the opening in a direction of the blast,such that a person can travel through the opening thereby created. 7.The method according to claim 6, wherein the explosive charge cuts atleast about 10% to 75% of the cut reinforcement members at one locationand the remainder at two locations.
 8. The method according to claim 6,wherein when double rebar is used the explosive charge cuts at least twoof the cut reinforcement members at one location and the remainder attwo locations.
 9. An initiation mechanism for igniting a linear shapedcharge comprising: a. a linear shaped charge having a metal liner; b. aplurality of detonators attached to the linear shaped charge; and c. amechanism for simultaneously igniting the plurality of detonators; andwherein the simultaneous ignition of the plurality detonators creates asubstantially planar detonation wave.
 10. A method of creating asubstantially planar detonation wave, the method comprising: a.providing a linear shaped charge having a metal liner; b. attaching aplurality of detonators to the linear shaped charge; and c. igniting theplurality of detonators with a mechanism for simultaneously igniting theplurality of detonators; and d. wherein the simultaneous ignition of theplurality detonators thereby creates a substantially planar detonationwave.
 11. An initiation mechanism for igniting a linear shaped chargecomprising: a. a linear shaped charge having a metal liner; b. a firstdetonator attached to the linear shaped charge; c. a second detonatorattached to the linear shaped charge; d. an intermediate detonatorattached to the linear shaped charge and disposed between the firstdetonator and the second detonator; and e. a mechanism forsimultaneously igniting the first, second, and intermediate detonators,and wherein the simultaneous ignition of the plurality first, second,and intermediate detonators thereby creates a substantially planardetonation wave.